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Dies and loses power after new fuel pump


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1987 gl 2 wd ea82 engine. Had some issues with stalling when I have extended idle time and or red lights (driving in town). Also had issues with it stuttering from 700-2500 rpm after a cold start. Issue went away after it warmed up. Fuel pump was also getting noisy after extended idle time. With the said issues, car still ran great at highway speeds and got 30-33 mpg.

 

Fast forward to this week, I decided the prior mentioned issues may be a weak and or clogged fuel pump. So i went ahead and replaced the fuel pump with an externally mounted 1987 ford ranger inline pump. The specs exceed the oem pump and delivers more volume and pressure 70-90 psi. I had some issues fitting the pump with the different hose diameters and pump is longer and bigger in diameter. After all was said and done, I installed the pump having to reduce the larger fuel line from the tank to around 3/8 when it got to the pump fitting. Also, i had to use some 3/8 stainless fuel line after to pump to get back to the oem fuel line from the pump.

 

After all this, car runs. Problem is, it loses power at around 2500 rpm starting. The loss of power is more extreme in a higher gear, leaving it hard to get up hills and accelerate above 55 mph. Once car has warmed, the engine likes to die after idling for about a minute. Car restarts just fine and repeats this issue.

 

None of these new symptoms existed prior to changing the fuel pump. The hesitation on cold starts appears to have gone away and been replaced by the loss of power at higher rpms. The new pump is obviously operating at a much higher rpm, maybe the fuel pressure is not being regulated properly? Also, when installing the new pump, i had to bend around some of the 28 year old metal fuel lines under the car. Maybe I cracked one and now I am pulling in air? Is it possible my fuel filter has clogged? Could the new pump be bad? (it is very noisy, but this pump is known for it. ) The pump strangely makes different pitched noise when car is idling. 

 

looking for opinions, thanks

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You have 2 posts that are similar. Im only going to reply to this one. I built my own bracket and used a lift pump on my ea81 brat. Details of my install are of little value to your conversion.

Your problem sounds like what I would expect from use of this pump. These things are poor pullers/suckers, they require a very good gravity feed, or a lift pump to feed them. What I suspect is that you have a "gpm" problem. At idle and low load it seems ok. Once under load the pump simply fails to deliver. To test this you need a fuel pressure gauge and a way to stub in to the delivery line. If that looked ok one would also have to be able to see it while driving under load.

For fun make sure the pump is well below the tank with a straight restriction free supply line. Give the pump a dedicated ground, and consider using 12 ga wiring from the battery through the relay to the pumps pigtail. Check ur battery connections and grounds.

The noise from the pump varies with engine speed and with electrical load? No suprise because its so noisy.

Tell us more about the gauge issue.

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There was a reason the stock pump had such a large line feeding it, and it had a good gravity feed. Could your problem be something else? Coincidences are never fun in the diagnostic world.

There is always the option of investing in a quality stock style fuel pump. If I didnt have, or want to invest in, proper diag tools this is the route Ide take.

Edited by ihscout54
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Not carbed, its an spfi ea82. 

 

I understand what your saying, I didn't thing the gravity feed would be this sensitive to change as far as line size and routing of the inlet hose. 

 

What I plan on doing to start is re do the inlet hose and put the larger fitting on the inlet side of the pump. This is probably the main issue. I have worked primarily on newer vehicles with in tank pumps, so I am not used to this situation.

 

The voltage gauge has been acting fine for a few days now, well see what happens. Prior to this though, the gauge would just bottom out like it was not working. I had no signs of low voltage when driving.

 

I will work on it on my next day off and report back. Thanks

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How far from the tank do you have this pump located? Definitely change the fuel filter. That should have been the first thing you tried as it's cheap to replace and super easy to get to.

 

The typical go to fuel pump is the older 80s f150 pumps from the dual tank trucks.

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Alright, I replaced the inlet fitting out for one that is 1/2 inch, which is bigger than oem. I also double checked the inlet hose, no kinks and is a straight shot to the fuel pump and running slightly downhill.

 

I bought a new fuel filter, but upon taking the old one off, I found no evidence of dirty fuel and also blew through the old one and it was like new. zero resistance. I am having doubts the fuel filter is a culprit.

 

To answer a previous question, the fuel pump is essentially mounted in the oem location. Only thing that really changed is that i had to add a 180 degree turn with steel fuel hose to return from the pump to the oem steel fuel line. This is on the outlet side, which means I doubt it causing any issues.

 

I am at a loss for what I should do next, the old fuel filter is only about 5 months old and clean based on my tests. I get paid once a month and money is super tight right now. So its hard to dive into teeing in a pressure gauge on the fuel line. 

 

As far as the wiring issue to the pump, maybe I am wrong, but in my mind if the voltage and wiring was sufficient for the old pump, why would it be for the new one? Albeit, the new one is a much higher psi and gpm pump, I would assume the wiring should support the pump. 

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So is it a possibility that my issue is the bigger pump on the smaller wiring? I have done a little research and found that this pump should only be drawing about 6 amps max. My guess based on my memory is the wiring is about 14 gauge to 16 gauge. A quick check of a 12 volt wire gauge table says at 6 amps, I need only 18 gauge wire at lengths up to 20 ft.

 

Also, calculating voltage drop at 13.5 volts and the ballpark wire length of about 15 ft drawing 6 amps, voltage drop is .3 volts which is 2.7%. This should not be an issue. 

 

I am willing to change out the wire eventually but do not feel it is actually an issue at this point. Is there a possibility there is an issue with the fuel regulator? What if I bought a faulty fuel pump?

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I would fit the old pump back in again and see how the car runs at that point. If it returns to the original problems then you can narrow the new problems down to your new lines and their adaptations, and or the new fuel pump. If the car runs just like it did before the new pump I'd first try exchanging the new pump for a different one. And go from there.

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Thanks I75eya, I did just that after my last post. I was having issues with even keeping the engine running and figured I would just revert to the oem pump.

 

All the issues associated with the new pump are gone. Engine idles fine, has good power through all gears, but my old issues returned. Fortunately I can live with that for now. Not sure what the new pump had going on, but even my voltage is back up above 12 again. Seems the new pump was defective somehow. 

 

Anyhow, the issues that returned are slight hesitation on a cold start through second gear. Goes away once warmed up. Secondly, when driving in town only, (extended stop times at lights and traffic or stopping off at a store), It will take off and have good power all the way through second gear, once I hit third, sometimes it start jerking and acting like it lost all power. Sometimes it even dies. This only occurs during in town driving. If I let off the gas, sometimes it goes away. If it does stall out, it restarts just fine.

 

There was one or two times a few months ago where the car did just this and would not start back up for probably 10 minutes of sitting. After which it ran like a top all the way home. Seems odd to me.

 

Today I cleaned the MAF. I have a 35 code which I have had for a long time. Sometimes it is accompanied by a 34 code. Both of those solenoids are stuck open and I even plugged the EGR valve hose and disconnected it from the solenoid, also I plugged the hose on the other side of that solenoid, which goes to the throttle body. I cant seem to see why I need to fix this issue aside from the engine code.

 

To give a little history, I have had some issues with high idle when cold. I chalk it up to the IAC. Cleaning it has improved some idle issues in the past, unplugging it connector when engine is cold causes it to die, which means its working in some sense. 

 

I have also replaced the TPS sensor and adjusted it according to the FSM. This improved some issues with hesitation and with the rpms when coasting in gear,

 

I am thinking some of my issues are related to the CTS but haven't had time to actually pull it off and test it. I have tested it on the car and it seemed to be in range, but it is hard to judge when you dont know the temperature of the engine coolant.

 

I appreciate all the help I have received thus far.

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Sucks that the new pump was bad right out of the box, especially so as it can't be returned.

 

Codes 34 and 35 are due to the windings of those solenoids being shot. Replace them with different solenoids, or wire in a 33 Ohm resistor in their place.

Toyota or Nissan has similar solenoids, just need to change the connector over to the Subaru type.

Need to get the codes cleared before you can really troubleshoot other issues.

 

The CTS can be some what in spec, but giving false temp reading to the ECU. In other words, It's Lying...

I replaced the one in my '88 with an IDI Brand 17-1233 Sensor, and BWD Brand 28419A connector.

Cut connector off old one and soldered it to the new connector leads.

Helped with cold start issue I was having, especially during the Winter cold.

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hoses of the FICD can get hard, crack, may leak at certain times/states of load /revs etc, fast idle control device same as IAC I think.

 

Maybe check or replace those hoses and clamps ?

 

Great to find a ring in fuel pump was the cause of the other new troubles

really need to try one fix at a time, so you can share the answer with us :)

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I have checked for vacuum  leaks by spraying around all the hoses and fittings. Everything seems to check out.

 

As far as the CTS is concerned, I have noticed there are not only three different sensors, but there is also something called an air charge sensor on rockauto. I am aware of the different one in reference to the fan, gauge, and one related to the ECU measuring the coolant temperature. 

 

http://www.rockauto.com/catalog/moreinfo.php?pk=39891&cc=1268467&jnid=700&jpid=0

 

It appears to look identical to the one on my car. I have also seen other forum members reference to using this sensor to replace the cts. 

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